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Accessing a JS variable from a different <script> block

I need to access a js variable declared in one block of a html page into another block of the same html page just so I can stop a ajax call that is being made, but I don't know how can I access a variable that was declared into another block. I can't merge the two blocks, everything else is on the table.
<script>
$(function() {
var term = new Terminal('#input-line .cmdline', '#container output');
term.init();
});
</script>
<script>
term.ajaxHandler.abort();//but how can I access the variable term from the block above,this will be inside a button later
</script>
Thanks in advance

The way your code example is described, it's not possible to reuse that variable. Because it is not bound to the window object, it's bound to the function that is self-executed. It's an example of a "safe" way of libraries not intervening with your own code.
You can however, since I guess by the syntax it's jQuery, hook into the jQuery ajax handling. Based on your requirements, to stop an ajax call, you need to listen to all ajax requests.
You could take a look at the jQuery ajax hooks, https://api.jquery.com/category/ajax/.
You could end up with something like:
$(document).ajaxSend(function(event, xhr, settings){
if (settings.url === "/your/url/to/abort") {
xhr.abort();
}
});

just declare var term above the function declaration
var term
function test1(){
term = 'hello there'
test2()
}
function test2(){
console.log(term)
}
test1()

ok, I managed to solve, basically I created a function only to abort the ajax request like this:
this.abortAjax = () => {
requestHandler.abort();
}
and then accessing it within terminal.js itself using the term object that was instantiated beforehand. After working around the code I was able to keep everything inside the terminal script and not splitted in the two parts, getting something like this:
function ShowLoadingScreen () {
var customElement = $("<div>", {
"class" : "btn btn-danger btn-lg",
"text" : "Abort",
"onclick": "term.abortAjax()"
});
$.LoadingOverlay("show", {
//image : "/static/loading.gif",
background : "rgba(204, 187, 0, 0.8)",
imageAnimation : "rotate_right",
//imageAutoResize : true,
text : "Loading...",
custom : customElement
});
}
function request (command) {
...
requestHandler = $.ajax({
url: _url,
beforeSend: function () { ShowLoadingScreen(); }, // <Show OverLay
type: 'GET',
dataType: 'json',
success: function (response) {
...
},
complete: function () { HideLoadingScreen(); } //<Hide Overlay
}).fail(function (jqXHR, textStatus, error) {
...
});
ShowLoadingScreen();
}
Thanks, everyone.

"i" value in JavaScript for loop is not being recognized in a jquery function

I'm using jQuery and ajax to open a bootstrap modal window. My code works perfectly when not in a loop, and my content is displayed appropriately in the modal window. But I have five modals on the page, and naturally I'd like to use a for loop so I don't repeat my code five times.
It seems like a no-brainer to write a for loop to execute the code five times, but somehow, there is a problem, and when I put the code into a for loop, the modal content will not show in the opened window.
Here is code that works how I need it, so the modal content from my modal1.php file shows in a modal popup window. Notice that the i variable is used three times; once in the jQuery selector, and twice in the $.ajax(...) area:
var i = 1;
$('#modal' + i).on('show.bs.modal', function(e) {
var id = e.relatedTarget.dataset.id;
$.ajax({
type:'post',
url:'modals/modal' + i + '.php',
data:{id:id},
success:function(data){
$('#modal' + i).html(data);
}
});
});
This code below uses the variable i the exact same way as the code above. However, with the code below, the modal1.php content does not show (nor do any of the other files named 'modal[i].php'). Instead, only a blank dark background appears when they are opened.
for (i = 1; i < 6; i++) {
$('#modal' + i).on('show.bs.modal', function(e) {
var id = e.relatedTarget.dataset.id;
$.ajax({
type:'post',
url:'modals/modal' + i + '.php',
data:{id:id},
success:function(data){
$('#modal' + i).html(data);
}
});
});
}
So I don't understand why the $.ajax() area of the code won't recognize the i variable in the for condition, but it will recognize it in the initial jQuery selector $('#modal' + i), which I've tested and found to be true. Is there a way I can write this loop so that the ajax area will recognize the i variable? Or is there a mistake in my code that I'm overlooking?
Incidentally, I've noticed that similar questions have been asked, but they have been downvoted for not being clearly written. I've read them all, and they don't answer the question that I have today.

The problem here is that you are (unintentionally) referencing a variable (i) via a closure.
Since scope is dictated by function in JavaScript, wrap your on usage with another (immediately invoked) function so a unique i is saved:
for (i = 1; i < 6; i++) {
(function() {
var iModalNumber = i;
$('#modal' + iModalNumber).on('show.bs.modal', function(e) {
var id = e.relatedTarget.dataset.id;
$.ajax({
type:'post',
url:'modals/modal' + iModalNumber + '.php',
data:{id:id},
success:function(data){
$('#modal' + iModalNumber).html(data);
}
});
});
}());
}
The reason that these questions get down-voted so much is because issues/misunderstanding of closures is so common. It is admittedly a difficult concept to grasp, and your question was well written.
More information: How do JavaScript closures work?

You could probably do this without using loop but using jQuery .each() and adding value attributes to your html elements. Warning... untested code ahead.
jQuery('.modal').each(function(){ // use a class instead of an id
$(this).on('show.bs.modal', function(e) { //use $(this) to target
var i = $(this).val(); // get the value id
var id = e.relatedTarget.dataset.id; // do your code
$.ajax({
type:'post',
url:'modals/modal' + i + '.php',
data:{id:id},
success:function(data){
$('#modal' + i).html(data);
}
});
});
});

Why a JavaScript function with some specific name is not working while others are?

A very interesting problem I am facing these days is regarding one of my JavaScript function. My JavaScript function with some specific name is not working but if I change its name to anything else then it is working. Have a look -
// function to retain the jquery ui css for toolbar
function retain_css() {
alert('hi');
$( "#new_sort_options" ).buttonset();
}
// new sort
$(document).on("click", ".new_sort_button", function() {
var order = $(this).val();
var make_id = $('#new_make_id').val();
$.ajax({
beforeSend : start_loader(),
type : 'POST',
url : '/ajax/new-sort.php',
data : 'order='+order+'&make_id='+make_id,
dataType : 'json',
success : function(data) {
$("#new_results_toolbar").html(data.toolbar);
$("#new_results").html(data.models);
retain_css();
end_loader();
}
});
});
But retain_css() is not working at all. Even alert() is not firing. But if i change its name to anything such as my_fun() then the code works. I don't understand why it is happening so? Any idea? Don't worry about end_loader() function as it has nothing to deal with my problem. I also changed the order of code when retain_css() was being used but didn't work.

Try not to create global functions because it may collide with other frameworks or libraries.
//define private namespace
window.user3779493Functions = {};
//define method
user3779493Functions.retain_css = function() { ... }
//call method
user3779493Functions.retain_css();

Some functions are already programmed like 'alert('hi');', that is a function called alert:
function alert() {
/* do something */
}
That function also doesn't work.

How to place a jQuery snippet into a global file

I have a JavaScript file here http://www.problemio.com/js/problemio.js and I am trying to place some jQuery code into it that looks like this:
$(document).ready(function()
{
queue = new Object;
queue.login = false;
var $dialog = $('#loginpopup')
.dialog({
autoOpen: false,
title: 'Login Dialog'
});
var $problemId = $('#theProblemId', '#loginpopup');
$("#newprofile").click(function ()
{
$("#login_div").hide();
$("#newprofileform").show();
});
// Called right away after someone clicks on the vote up link
$('.vote_up').click(function()
{
var problem_id = $(this).attr("data-problem_id");
queue.voteUp = $(this).attr('problem_id');
voteUp(problem_id);
//Return false to prevent page navigation
return false;
});
var voteUp = function(problem_id)
{
alert ("In vote up function, problem_id: " + problem_id );
queue.voteUp = problem_id;
var dataString = 'problem_id=' + problem_id + '&vote=+';
if ( queue.login = false)
{
// Call the ajax to try to log in...or the dialog box to log in. requireLogin()
}
else
{
// The person is actually logged in so lets have him vote
$.ajax({
type: "POST",
url: "/problems/vote.php",
dataType: "json",
data: dataString,
success: function(data)
{
alert ("vote success, data: " + data);
// Try to update the vote count on the page
//$('p').each(function()
//{
//on each paragraph in the page:
// $(this).find('span').each()
// {
//find each span within the paragraph being iterated over
// }
//}
},
error : function(data)
{
alert ("vote error");
errorMessage = data.responseText;
if ( errorMessage == "not_logged_in" )
{
//set the current problem id to the one within the dialog
$problemId.val(problem_id);
// Try to create the popup that asks user to log in.
$dialog.dialog('open');
alert ("after dialog was open");
// prevent the default action, e.g., following a link
return false;
}
else
{
alert ("not");
}
} // End of error case
}
}); // Closing AJAX call.
};
$('.vote_down').click(function()
{
alert("down");
problem_id = $(this).attr("data-problem_id");
var dataString = 'problem_id='+ problem_id + '&vote=-';
//Return false to prevent page navigation
return false;
});
$('#loginButton', '#loginpopup').click(function()
{
alert("in login button fnction");
$.ajax({
url:'url to do the login',
success:function() {
//now call cote up
voteUp($problemId.val());
}
});
});
});
</script>
There are two reasons why I am trying to do that:
1) I am guessing this is just good practice (hopefully it will be easier to keep track of my global variables, etc.
2) More importantly, I am trying to call the voteUp(someId) function in the original code from the problemio.js file, and I am getting an error that it is an undefined function, so I figured I'd have better luck calling that function if it was in a global scope. Am I correct in my approach?
So can I just copy/paste the code I placed into this question into the problemio.js file, or do I have to remove certain parts of it like the opening/closing tags? What about the document.ready() function? Should I just have one of those in the global file? Or should I have multiple of them and that won't hurt?
Thanks!!

1) I am guessing this is just good practice (hopefully it will be
easier to keep track of my global variables, etc.
Yes and no, you now have your 'global' variables in one spot but the chances that you're going to collide with 'Global' variables (ie those defined by the browser) have increased 100% :)
For example say you decided to have a variable called location, as soon as you give that variable a value the browser decides to fly off to another URL because location is a reserved word for redirecting.
The solution to this is to use namespacing, as described here
2) More importantly, I am trying to call the voteUp(someId) function
in the original code from the problemio.js file, and I am getting an
error that it is an undefined function, so I figured I'd have better
luck calling that function if it was in a global scope. Am I correct
in my approach?
Here's an example using namespacing that will call the voteUp function:
(function($) {
var myApp = {};
$('.vote_up').click(function(e) {
e.preventDefault();
myApp.voteUp();
});
myApp.voteUp = function() {
console.log("vote!");
}
})(jQuery);
What about the document.ready() function? Should I just have one of
those in the global file? Or should I have multiple of them and that
won't hurt?
You can have as many document.ready listeners as you need, you are not overriding document.ready you are listening for that event to fire and then defining what will happen. You could even have them in separate javascript files.

Be sure your page is finding the jquery file BEFORE this file is included in the page. If jquery is not there first you will get function not defined. Otherwise, you might have other things conflicting with your jquery, I would look into jquery noConflict.
var j = jQuery.noConflict();
as seen here:
http://api.jquery.com/jQuery.noConflict/
Happy haxin
_wryteowl

Extending what KreeK has already provided: there's no need to define your "myApp" within the document ready function. Without testing, I don't know off the top of my head if doing so is a potential source for scope issues. However, I CAN say that the pattern below will not have scope problems. If this doesn't work, the undefined is possibly a script-loading issue (loading in the right order, for example) rather than scope.
var myApp = myApp || {}; // just adds extra insurance, making sure "myApp" isn't taken
myApp.voteUp = function() {
console.log("vote!");
}
$(function() { // or whatever syntax you prefer for document ready
$('.vote_up').click(function(e) {
e.preventDefault();
myApp.voteUp();
});
});

jQuery: Referencing the calling object(this) when the bind/click event is for a class

Thanks for reading this.
I am dynamically generating some data which includes a select drop-down with a text box next to it. If the user clicks the select, I am dynamically populating it (code below). I have a class on the select and I was hoping the following code would work. I tested it with an ID on the select and putting the ONE on the ID I got it to work. However, in changing the code to reference a class (since there will be multiple data groups that include a select with a text box next to it) and $(this), I could not get it to work. Any ideas would be helpful. Thanks
The relevance of the text box next to the select is the second part of the code...to update the text box when an option is selected in the select
.one is so the select is updated only once, then the .bind allows any options selected to be placed in the adjacent text box.
$('.classSelect').one("click",
function() {
$.ajax({
type: "post",
url: myURL ,
dataType: "text",
data: {
'_service' : myService,
'_program' : myProgram ,
'param' : myParams
},
success:
function(request) {
$(this).html(request); // populate select box
} // End success
}); // End ajax method
$(this).bind("click",
function() {
$(this).next().val($(this).val());
}); // End BIND
}); // End One
<select id="mySelect" class="classSelect"></select>
<input type="text">

$(this) is only relevant within the scope of the function. outside of the function though, it loses that reference:
$('.classSelect').one("click", function() {
$(this); // refers to $('.classSelect')
$.ajax({
// content
$(this); // does not refer to $('.classSelect')
});
});
a better way to handle this may be:
$('.classSelect').one("click", function() {
var e = $(this);
$.ajax({
...
success : function(request) {
e.html(request);
}
}); // end ajax
$(this).bind('click', function() {
// bind stuff
}); // end bind
}); // end one
by the way, are you familiar with the load() method? i find it easier for basic ajax (as it acts on the wrapped set, instead of it being a standalone function like $.ajax(). here's how i would rewrite this using load():
$('.classSelect').one('click', function() {
var options = {
type : 'post',
dataType : 'text',
data : {
'_service' : myService,
'_program' : myProgram ,
'param' : myParams
}
} // end options
// load() will automatically load your .classSelect with the results
$(this).load(myUrl, options);
$(this).click(function() {
// etc...
}); // end click
}); // end one

I believe that this is because the function attached to the success event doesn't know what 'this' is as it is run independently of the object you're calling it within. (I'm not explaining it very well, but I think it's to do with closures.)
I think if you added the following line before the $.ajax call:
var _this = this;
and then in the success function used that variable:
success:
function(request) {
_this.html(request); // populate select box
}
it may well work

That is matching one select. You need to match multiple elements so you want
$("select[class='classSelect']") ...

The success() function does not know about this, as any other event callback (they are run outside the object scope).
You need to close the variable in the scope of the success function, but what you really need is not "this", but $(this)
So:
var that = $(this);
... some code ...
success: function(request) {
that.html(request)
}

Thanks Owen. Although there may be a better to write the code (with chaining)....my problem with this code was $(this) was not available in the .ajax and .bind calls..so storing it in a var and using that var was the solution.
Thanks again.
$('.classSelect').one("click",
function() {
var e = $(this) ;
$.ajax({
type: "post",
url: myURL ,
dataType: "text",
data: {
'_service' : myService,
'_program' : myProgram ,
'param' : myParams
},
success:
function(request) {
$(e).html(request); // populate select box
} // End success
}); // End ajax method
$(e).one("click",
function() {
$(e).next().val($(e).val());
}); // End BIND
}); // End One